


Sinful

by sadmacedace



Series: Haikyuu!! Incubus AU [1]
Category: Haikyuu!!
Genre: Anal Fingering, Anal Sex, Blowjobs, Incubus Sugawara, M/M, Rimming, incubus au, magic users exist in universe
Language: English
Status: Completed
Published: 2016-06-04
Updated: 2016-06-05
Packaged: 2018-07-12 06:04:37
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 3,556
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7088215
Author URL: https://archiveofourown.org/users/sadmacedace/pseuds/sadmacedace
Summary: <blockquote class="userstuff">
              <p>Suga is an incubus, and he's become addicted to feeding on a certain person.</p>
            </blockquote>





	1. Sinful

Suga is an incubus.

There is a common misconception about incubi. While they did feed on life energy of humans who slept, they never had sex with them, and they never took so much energy from them that they would die. These were unwritten rules in polite incubi society. Although some incubi did ignore the no sex rule. While there were plenty of ways to draw out energy from humans, sex drew out the most potent energy from humans. But this of course left after effects on the human such as exhaustion, migraine, and loss of appetite to name a few.

But Suga preferred to use his magics to give them sweet dreams, these dreams would slowly absorb small amounts of energy from humans over a long period of time. While it was tedious to some, Suga felt it was the least invasive way to sate his hunger. He was fine with this process. Until he became addicted to the energy of a particular man.

It was during the dead of night he would visit him. Suga would watch from outside the man's window, making sure he was truly asleep. Then would transform himself into smoke and slipped through the cracks in the windowpane to reform once in the man’s room.

The man was in his usual sleeping position, lying on his stomach with his head turned to the side. Suga cast a simple dream spell, however this one didn’t absorb energy, Suga had started using a different technique to draw energy from the man. The dream spell was just a precaution to keep the man from waking during Suga’s feeding.

Suga touched the man’s back, feeling the head underneath his fingertips he shuddered. Salacious thoughts flickered into his mind, he shook his head. He needed to focus, if he didn’t he would risk his spell wearing off or even worse - overfeeding.

He carefully straddled the man. When he was in a comfortable position and checking to make sure the man wasn’t awake, he began to massage the pads of his fingers into the tanned skin beneath him. He started to slowly work out the small knots in the man’s shoulders pushing and holding where he needed to relax any tired muscles. Suga smiled when he heard a content sigh come from the man underneath him - human’s were surprisingly honest during sleep.

He then worked his way down the man’s back firmly circling his thumbs on either side of his spine, gently pushing down with the palm of his hand when finding any tight spots. Making his way to the lower back easing out any tension there, then worked his way back up the man’s back. Feeling the muscles relaxed under his fingertips he started to use his magic to absorb some of the man’s energy.

Suga started giving the man massages a few weeks ago, around that time he also started weekly visits to the man’s house rather than monthly ones. Suga knew he shouldn’t have made himself a regular, but something inside him sparked a need to keep coming back to feed off the man. Since he started feeding on this man he hasn’t felt a desire to feed on anyone else. He only took just enough energy to get him through the week since he was using physical contact now, rather than using dream absorption. While it didn’t absorb as much as _other_ forms of physical contact, it took more than using dreams did.

He felt tingling starting to crawl up his arms. His breath hitched. It felt good, almost too good. Impure thoughts flickered in his mind. If absorbing energy with such a small amount of touch felt this good, what would sex feel like? There was no doubt that the man under him was attractive. Dark hair, and tanned skin, and just muscular enough for Suga’s liking. What kind of lover would he be? Passionate and intense he imagined. Probably preferred to hold his partner than be held. Judging by how fit he was, he would have stamina too.

Suga hadn’t realized he was hard and grinding against the man until he was shaken out of this thoughts from a groan underneath him. He immediately froze, stopping all movements in hopes that he hadn’t awoken the man. Staying silent and as still as he could he watched over the man he was certain the man was still asleep. He let out a sigh of relief. He probably had taken enough energy now. It was time to leave.

He slowly moved off of the man now standing upright and taking one last look at his face. Seeing how relaxed he looked made Suga’s heart flutter. It made him happy to make him feel good. He glanced over the man’s lips. Suga bit his lip. He felt tempted to kiss him. He knew he shouldn’t, but before he could rationalize with himself he was already closing the distance between them. Well, surely a goodbye kiss wouldn’t hurt.

Before he could place the kiss, Suga found himself being pulled forward and pushed face down onto the bed.

“Finally caught you.” a deep voice chuckled behind him.

Suga’s first reaction was to turn into smoke and escape the situation, but when he tried to access his magic he found he couldn’t cast any spells. He froze, this man wasn’t a normal human. Whatever he was he was able to use his own magic to neutralize Suga’s spells.

“You’ve been giving me some trouble.” he said.

“I-I’m sorry.” Suga said meekly. Not wanting to anger the man further.

Suga felt the hand that was pressed to his back tense.

“Hey, I didn’t mean to scare you. I just wanted to talk.” the man soothed. Suga felt his hand withdraw and he sat up.

The man was sitting on his bed, still quite in close proximity to Suga. Dark eyes surveyed Suga’s body.

“You look pretty unusual for an incubus. I was expecting bat wings and horns” he said quirking a brow.

“N-not all incubi look like that, the one’s who do, do it just for the looks.” Suga responded, still unsure of what to do.

“Though your outfit does seem to scream ‘I’m an incubus’.” he gestured to the black catsuit Suga was wearing.

“It’s actually pretty modest by incubi standards.” he quipped. The man next to him let out a unabashed laugh.

“I suppose so. I’m Daichi by the way. And you’ve been causing me some trouble.” he spoke softly looking at Suga through half lidded eyes.

“I’m Suga. And I-I’m sorry, I didn’t think I was taking that much energy from you. I’m so sorry, I’ll stop feeding-” Suga was cut off before he could finish.

“The feeding isn’t a problem. I’m sure you’re aware I’m not a formal human, I’m a mage, a human blessed with the ability to wield magics. So I have much more life energy than your average human does. But for the past few weeks I’ve been getting dreams that have been very… distracting for me when I wake.” Daichi drawled on.

“What kind of dreams?” Suga inquired.

“Well… this is pretty embarrassing to admit, but I’ve been having… sexual dreams. Waking up like that can be pretty inconvenient, and the thoughts linger with me all day - sometimes for half the week.” he admitted.

“I… I haven’t been giving you those kinds of dreams.” Suga responded tilting his head slightly. Maybe another incubus was feeding from Daichi during the days he wasn’t there. He felt a bite of jealousy in his chest.

“Maybe not, but the unconscious mind does wander, especially one getting those amazing massages. By the looks of it you felt good too.” Daichi smirked. Suga’s eyes widened.

“How long were you awake?” he asked.

“From the moment you started to grind against me.” he said casually. Suga’s mouth dropped in shock.

“I’m so sorry. I swear I didn’t mean to do that.” Suga said earnestly. Daichi waved a hand.

“I’m not angry. But I want to ask something. How far would you have gone if I didn’t disturb you?” he asked. Suga could have sworn he saw a quick smirk.

“I wouldn’t- Not with out your- I mean I’ve never -” Suga wasn’t quite sure what to say, he’s never had sex with a human before, he hasn’t even done that with other incubi.

“Would you like to continue?” Daichi asked.

Suga stared at him, eyes wide and mouth agape. He was not expecting that! He caught himself before he instinctively replied ‘yes’.

“You don’t have to, it’s just you’ve been giving me blue balls all week, and if you wanted to…” Daichi started to trail off.

“W-what if I overfeed?” Suga asked looking through his thick lashes. He was tempted, but he was still apprehensive about a lot of things, and… were they getting closer?

Daichi cupped his cheek and ran a thumb over his lips.

“I told you already, you don’t need to worry about that.” He hummed. Inching closer so his lips just brushed against Sugas, giving Suga the option of closing the gap between them.

And he did.

Suga felt a hand move to the back of his head pulling him deeper into the kiss. Suga moved his hands to grasp onto Daichi’s shoulders, letting himself submit to the kiss. He felt Daichi lick against his lips, asking for access into Suga’s mouth. Suga felt Daichi’s tongue flick against his own. He let out a pleasured moan that was swallowed down by Daichi’s own mouth. He was pushed gently back down onto the bed. Daichi pulled away and started to suck and nip at his neck. He ran his hands over Suga’s chest, finding his nipples and thumbing them through the fabric. Suga felt himself harden as Daichi played with his nipples.

“So how do you take this thing off?” Daichi pulled back from his neck and nodded at his catsuit.

Suga let out an ‘oh’ before sweeping a hand across his chest, casting another spell and the fabric started to dissipate. Daichi hummed joyfully when he had access to the skin underneath. Feeling the direct contact sent chills up Suga’s spine, he wasn’t actively absorbing energy from Daichi, but he was feeling the pleasure that came with feeding. He started to see why other incubi chose this way of feeding.

When Daichi was finished with teasing his nipples until they were pert and flushed he moved down towards Suga’s cock leaving deep purple hickies along the way. Daichi kissed Suga’s hips before taking a hold of his cock and licking from the base to the tip. Suga whimpered. Daichi sucked at the sides before teasing the tip with his tongue. Suga bit his lip to try and suppress a moan but it managed to break through. He heard Daichi let out a pleased sigh before he took Suga’s dick into his mouth. Suga threw his head back and moaned. Daichi’s mouth was warm and wet around his cock. Suga wasn’t sure how long he would last if Daichi kept sucking on him like this.

“Dai- Daichi, please.” he gasped.

Before reaching his peak Daichi pulled off his cock and moved back. Suga was about to let free a whine but Daichi grabbed onto his hips and dragged him up so his ass was at the same height as Daichi’s face. Being in such a shameless position made his cheeks burn. He didn’t have long to feel embarrassed before he felt Daichi’s tongue on his hole.

Feeling Daichi’s tongue licking around the rim before prodding his tongue into Suga’s entrance made it feel like small bursts of static electricity was running up his spine. Suga was moaning shamelessly, he never thought he would ever find himself in this sort of position, yet here he was. Moaning and writhing in the bed of his feed. Though he wasn’t sure if he cared anymore. He felt Daichi slip a finger in and open him up. Daichi brushed gently against his prostate making Suga writhe and arch his back. He felt another finger slip in, opening him up more, he could feel how gentle Daichi was being, while his movements were with purpose they weren’t without care. Feeling the third finger push into him and Suga felt exposed. Daichi was fingering him open and still licking at the rim of his hole. His cock was leaking pre-seed onto his stomach, but he didn’t care. He just didn’t want Daichi to stop.

He whined when Daichi removed his fingers and laid him back down onto the bed. Daichi leaned forwards, giving Suga a quick peck on his lips.

“I don’t suppose you know any lubrication spells? I didn’t really prepare.” Daichi asked running his hands over Suga’s chest again.

Suga nodded, he knew of one. It was a simple spell, but it would do what they needed. He reached down wrapping a hand around Daichi’s dick, he felt his own twitch when Daichi groaned. Stroking from the base to the tip he started using his magic to slick Daichi’s cock. Hearing Daichi’s groans pleased him, they were probably Suga’s favourite sounds now. When enough lube was applied to Daichi’s cock he pulled back. He looked up at Daichi through half lidded eyes, letting Daichi know he was done.

Daichi leant down and captured his lips once again. He felt Daichi’s cock prod at his hole before slowly pushing forward entering him. Daichi gently seated himself inside of Suga. Not pushing too roughly to give Suga time to adjust.

“Gods you’re tight.” Daichi moaned against his lips and pulled back to look at him. “Are you okay?” he added. Suga nodded

“I’m fine, you’re pretty big.” he sighed out.

“I’ll take that as a compliment.” Daichi chuckled.

When Suga got used to the feeling of Daichi inside him, he told Daichi it was okay to move. Daichi complied. Drawing his hips back until his tip was just inside of Suga, then pushed back inside of him. Daichi had set a steady pace. Still with the same care and gentleness as before. It didn’t take long for Suga to start feeling good. Static electricity shuddering up his spine whenever Daichi grazed over his prostate. The feeling was intense. He felt himself starting to become incoherent when Daichi started to thrust into him more earnestly.

“You can start to feed now.” Daichi told him.

“Okay.” Suga responded, breath hitching.

Suga started a spell that would absorb energy through touch. When he did he instantly felt his pleasure spike. He moaned loudly and shamelessly. He’s never felt something like this in his life. Sparks ran up his back and blossomed in his chest whenever Daichi directed his thrusts to Suga’s prostate. Daichi grabbed onto his thighs and pushed them up, to thrust deeper into Suga. He writhed and arched his back. With his pleasure heightened from feeding, and Daichi alternating between deep thrusts and shallow ones to brush against his prostate. Suga knew he was going to climax. He reached up and dug his fingernails into Daichi’s shoulders. Trying to hold off his peak.

“Daichi- I’m gonna come.” he said desperately.

“Do it. Come for me.” Daichi moaned, pistoning his hips into Suga.

Despite his best efforts he couldn’t hold back. He felt himself tense up as he came onto his stomach. He felt himself tighten around Daichi’s cock. Hearing a surprised groan from him and he felt Daichi spill his own seed into him. Daichi hunched over him and rested his forehead on Suga’s shoulder. Suga stopped his feeding spell and let himself calm down with Daichi.

When their breathing evened Daichi pulled back and placed a kiss on Suga’s forehead.

“That was amazing. You were amazing.” Daichi sighed contently.

“You were pretty amazing yourself.” Suga chuckled. “I don’t think I’ll ever be able to feed on anyone else again.” he added.

“Why don’t you just feed on me from now on?” Daichi asked.

“I wouldn’t want to impose.” Suga started.

“I wouldn’t mind, actually, I don’t like the thought of sharing you with anyone else.” Daichi admitted. Suga could see the red in his cheeks, and that wasn’t because of their earlier actions.

“Well... I already stopped feeding on others when I found you. Now you’ve completely ruined me being able to feed on others.” Suga smirked at him.

“Then I take full responsibility.” Daichi smiled back at him.

They shared another sensual kiss when Suga felt Daichi’s cock twitch inside him, he felt his own start to harden in response.

“Want to go again?” Daichi hummed. Suga grinned back at him.

“Definitely.”


	2. Morning After

**Summary for the Chapter:**

> The morning after. Daichi's POV.

When he awoke he felt the warmth of a body next to him, skin flush against his. He moved back to look at the man lying next to him, Suga was facing away from him, his dove-grey hair tousled from sleep and sex. Daichi eyed his back, milky skin adorned with small and large hickies. He ran his hands over Suga’s arm and kissed his back.

“Morning.” he heard Suga hum.

“Morning.” he responded moving up to kiss Suga on the cheek.

Daichi lay back down and tucked his face in the space between Suga’s neck, grinning as he remembered last night.

“I’ve never done it with an incubus before.” he joked.

“That makes two of us.” Suga chucked in response.

When the words finally registered in his groggy-from-sleep brain Daichi tensed. That night when Suga mentioned he hadn’t done it before. Was he talking about with anyone? Daichi sat up and looked at the man beside him. Suga had turned to look at him, a confused expression on his face.

“Is everything okay?” Suga asked looking up at him, his amber eyes looking brighter than they did than last night. Daichi opened his mouth but he wasn’t quite sure how to ask.

“When you said you hadn’t done it before. Where you just talking about humans or did you mean overall?” he questioned

Suga’s eyes widened, and a blush crept across his cheeks, obviously taken back by the question. Daichi saw his tongue peek out to wet his lips.

“I- I’ve never done it with anyone. You… You’re my first.” Suga responded biting his lip.

Daichi was speechless, he was caught between wanting to lean down and ravish the incubus with kisses and concern that he pushed Suga too far.

“W-was it okay? I mean- Was I too forward? Are you okay with me- that it was me?--” before he could continue with his tangent he felt Suga’s soft hand cup his cheek.

“I’m okay. I’ve… never felt that good before. And I’m glad it was with you.” Suga said softly, rubbing his thumb against Daichi’s cheek.

Daichi’s worry faded away with Suga’s soothing words and gentle touch. He smiled softly at Suga.

“I think I might just be in love with you.” he confessed. Not really thinking through what he was saying. Suga let out a pleased hum.

“I’m not sure what love is like. But I- I would like to stay with you.” Suga admitted, voice still gentle and soothing.

“Not to mention, you’re responsible for feeding me now.” he added with a grin pushing his hand back to run his fingers through Daichi’s hair.

Daichi’s smile widened. “Of course.”

He leant down and pecked Suga’s lips. Moving down to his neck to suck on the skin there. Suga gladly accepted him. Leaving more hickies to add to the ones he made last night. He kissed down Suga’s clavicle to his chest, where he took a pink nipple into his mouth, grinning when he heard a gasp from Suga. Circling the tender flesh he moved a hand to tease at the other nipple, gently thumbing it between his thumb and index finger. He felt Suga arch under him. Hearing his quiet breathy moans made Daichi’s cock twitch. He felt himself growing hard.

Finishing his gentle teasing on Suga’s nipples he licked and kissed his way down Suga’s stomach, making his way to Suga’s hipbones. 

Before he could get any further his bedroom door swung open. He jolted upright to see Asahi - his roommate - standing in the doorway with a distressed expression on his face.

“Daichi- There’s something wrong with Noy-ah!” Asahi stood there with the kind of expression you would expect when you just walked in on your friend about to have sex.

“I-I’m sorry I didn’t know you had company… I-I’ll wait for you out here.” he added before shutting the door with a little too much force.

Daichi let out a tired sigh. “Not exactly how I wanted your first meeting to go. Meet the roommate.”

Daichi looked down at Suga who was bright red. Suga gave him a small ‘ah’ in response.

“I should go and make sure he’s okay” Daichi started, somewhat reluctant to leave what they just started. “Actually, I could use your help. Noya is an incubus too.” he added.

“He is? Okay.” Suga agreed, the blush from before starting to leave his face.

Daichi leant down once more but stopping just as their lips touched.

“When we’re done I’m going to bring you back here and make love to you until you can’t remember your own name.” he whispered and closed the space between them.

He felt Suga shudder beneath him. He couldn’t wait for later. 

**Notes for the Chapter:**

> Felt like there needed to be a morning after.

**Author's Note:**

> This was all an excuse to write porn.  
> Comments = love.


End file.
